/*
 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 */
package javax.swing.text;

import java.awt.*;
import javax.swing.Icon;
import javax.swing.event.*;

/**
 * Icon decorator that implements the view interface.  The
 * entire element is used to represent the icon.  This acts
 * as a gateway from the display-only View implementations to
 * interactive lightweight icons (that is, it allows icons
 * to be embedded into the View hierarchy.  The parent of the icon
 * is the container that is handed out by the associated view
 * factory.
 *
 * @author Timothy Prinzing
 */
public class IconView extends View {

  /**
   * Creates a new icon view that represents an element.
   *
   * @param elem the element to create a view for
   */
  public IconView(Element elem) {
    super(elem);
    AttributeSet attr = elem.getAttributes();
    c = StyleConstants.getIcon(attr);
  }

  // --- View methods ---------------------------------------------

  /**
   * Paints the icon.
   * The real paint behavior occurs naturally from the association
   * that the icon has with its parent container (the same
   * container hosting this view), so this simply allows us to
   * position the icon properly relative to the view.  Since
   * the coordinate system for the view is simply the parent
   * containers, positioning the child icon is easy.
   *
   * @param g the rendering surface to use
   * @param a the allocated region to render into
   * @see View#paint
   */
  public void paint(Graphics g, Shape a) {
    Rectangle alloc = a.getBounds();
    c.paintIcon(getContainer(), g, alloc.x, alloc.y);
  }

  /**
   * Determines the preferred span for this view along an
   * axis.
   *
   * @param axis may be either View.X_AXIS or View.Y_AXIS
   * @return the span the view would like to be rendered into Typically the view is told to render
   * into the span that is returned, although there is no guarantee. The parent may choose to resize
   * or break the view.
   * @throws IllegalArgumentException for an invalid axis
   */
  public float getPreferredSpan(int axis) {
    switch (axis) {
      case View.X_AXIS:
        return c.getIconWidth();
      case View.Y_AXIS:
        return c.getIconHeight();
      default:
        throw new IllegalArgumentException("Invalid axis: " + axis);
    }
  }

  /**
   * Determines the desired alignment for this view along an
   * axis.  This is implemented to give the alignment to the
   * bottom of the icon along the y axis, and the default
   * along the x axis.
   *
   * @param axis may be either View.X_AXIS or View.Y_AXIS
   * @return the desired alignment &gt;= 0.0f &amp;&amp; &lt;= 1.0f.  This should be a value between
   * 0.0 and 1.0 where 0 indicates alignment at the origin and 1.0 indicates alignment to the full
   * span away from the origin.  An alignment of 0.5 would be the center of the view.
   */
  public float getAlignment(int axis) {
    switch (axis) {
      case View.Y_AXIS:
        return 1;
      default:
        return super.getAlignment(axis);
    }
  }

  /**
   * Provides a mapping from the document model coordinate space
   * to the coordinate space of the view mapped to it.
   *
   * @param pos the position to convert &gt;= 0
   * @param a the allocated region to render into
   * @return the bounding box of the given position
   * @throws BadLocationException if the given position does not represent a valid location in the
   * associated document
   * @see View#modelToView
   */
  public Shape modelToView(int pos, Shape a, Position.Bias b) throws BadLocationException {
    int p0 = getStartOffset();
    int p1 = getEndOffset();
    if ((pos >= p0) && (pos <= p1)) {
      Rectangle r = a.getBounds();
      if (pos == p1) {
        r.x += r.width;
      }
      r.width = 0;
      return r;
    }
    throw new BadLocationException(pos + " not in range " + p0 + "," + p1, pos);
  }

  /**
   * Provides a mapping from the view coordinate space to the logical
   * coordinate space of the model.
   *
   * @param x the X coordinate &gt;= 0
   * @param y the Y coordinate &gt;= 0
   * @param a the allocated region to render into
   * @return the location within the model that best represents the given point of view &gt;= 0
   * @see View#viewToModel
   */
  public int viewToModel(float x, float y, Shape a, Position.Bias[] bias) {
    Rectangle alloc = (Rectangle) a;
    if (x < alloc.x + (alloc.width / 2)) {
      bias[0] = Position.Bias.Forward;
      return getStartOffset();
    }
    bias[0] = Position.Bias.Backward;
    return getEndOffset();
  }

  // --- member variables ------------------------------------------------

  private Icon c;
}
